Relationship between Feet Position and Anterior-posterior Center of Pressure (COP) location - What are the Determining Factors in the Adjustment of Center of Gravity?

摘要

Postural control is defined as the ability to maintain equilibrium in a gravitational field by keeping or returning the center of body mass over its base of support1). The center of body mass over its base of support is the center of pressure (COP) within the base of support (BOS). Maintaining the COP within the BOS prevents a subject from falling in a static situation. Moreover, an effective BOS adjustment during a COP deviation from the BOS can lead to dynamic fall prevention. Scientifically, the steadiest postural stability is achieved when the COP is located at the center of the BOS area. However, humans don't necessarily stand with COP located at the center of the BOS. In addition, if COP deviates from the BOS, the subject would make a step to position COP within the newly created BOS restoring stability. Postural sway has been measured in standing posture with various feet positions, and postural control strategies have been considered in various studies2"5). However, the determining factor of the location of COP in one-foot standing and in tandem standing have not been adequately studied.